:root {
  --bg: #ffffff;
  --bg-sidebar: #fafafa;
  --bg-bubble-user: #f2f2f3;
  --bg-raised: #ffffff;
  --bg-hover: #e9e9eb;
  --text: #0a0a0a;
  --text-dim: #6f6f75;
  --border: rgba(10, 10, 10, 0.13);
  --border-strong: rgba(10, 10, 10, 0.22);
  --accent: #00c853;
  --accent-2: #00e676;
  --accent-hover: #00b34a;
  --accent-text: #06170d;
  --accent-glow: rgba(0, 200, 83, 0.3);
  --accent-wash: rgba(0, 200, 83, 0.07);
  --code-bg: #f5f5f6;
  --radius-xs: 5px;
  --radius-sm: 9px;
  --radius-md: 11px;
  --radius-lg: 16px;
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 2px 8px rgba(0, 0, 0, 0.06), 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow-lg: 0 8px 28px rgba(0, 0, 0, 0.1), 0 2px 6px rgba(0, 0, 0, 0.06);
  --ease: cubic-bezier(0.16, 1, 0.3, 1);
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #0a0a0b;
    --bg-sidebar: #0d0d0f;
    --bg-bubble-user: #1a1a1d;
    --bg-raised: #131315;
    --bg-hover: #27272b;
    --text: #f2f2f3;
    --text-dim: #8b8b91;
    --border: rgba(255, 255, 255, 0.12);
    --border-strong: rgba(255, 255, 255, 0.22);
    --accent: #00e676;
    --accent-2: #69f0ae;
    --accent-hover: #00c853;
    --accent-text: #06170d;
    --accent-glow: rgba(0, 230, 118, 0.4);
    --accent-wash: rgba(0, 230, 118, 0.09);
    --code-bg: #0f0f11;
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 2px 10px rgba(0, 0, 0, 0.4), 0 1px 3px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 12px 36px rgba(0, 0, 0, 0.55), 0 2px 8px rgba(0, 0, 0, 0.4);
  }
}

:root[data-theme="dark"] {
  --bg: #0a0a0b;
  --bg-sidebar: #0d0d0f;
  --bg-bubble-user: #1a1a1d;
  --bg-raised: #131315;
  --bg-hover: #27272b;
  --text: #f2f2f3;
  --text-dim: #8b8b91;
  --border: rgba(255, 255, 255, 0.12);
  --border-strong: rgba(255, 255, 255, 0.22);
  --accent: #00e676;
  --accent-2: #69f0ae;
  --accent-hover: #00c853;
  --accent-text: #06170d;
  --accent-glow: rgba(0, 230, 118, 0.4);
  --accent-wash: rgba(0, 230, 118, 0.09);
  --code-bg: #0f0f11;
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 2px 10px rgba(0, 0, 0, 0.4), 0 1px 3px rgba(0, 0, 0, 0.3);
  --shadow-lg: 0 12px 36px rgba(0, 0, 0, 0.55), 0 2px 8px rgba(0, 0, 0, 0.4);
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  height: 100%;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Inter, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  -webkit-font-smoothing: antialiased;
  letter-spacing: -0.006em;
}

body { transition: background 0.2s var(--ease), color 0.2s var(--ease); }

.hidden { display: none !important; }

::selection { background: var(--accent-glow); }

.messages, .history-list, .bubble pre code {
  scrollbar-width: thin;
  scrollbar-color: var(--border-strong) transparent;
}
.messages::-webkit-scrollbar, .history-list::-webkit-scrollbar, .bubble pre code::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}
.messages::-webkit-scrollbar-thumb, .history-list::-webkit-scrollbar-thumb {
  background: var(--border-strong);
  border-radius: 8px;
}
.messages::-webkit-scrollbar-thumb:hover, .history-list::-webkit-scrollbar-thumb:hover {
  background: var(--text-dim);
}

button { font-family: inherit; }
button:focus-visible, input:focus-visible, textarea:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

/* Gate screen */
.gate {
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  background:
    linear-gradient(var(--border) 1px, transparent 1px) 0 0 / 100% 42px,
    linear-gradient(90deg, var(--border) 1px, transparent 1px) 0 0 / 42px 100%,
    var(--bg);
  background-size: 42px 42px, 42px 42px, auto;
  -webkit-mask-image: radial-gradient(ellipse 70% 70% at 50% 50%, #000 40%, transparent 90%);
  mask-image: radial-gradient(ellipse 70% 70% at 50% 50%, #000 40%, transparent 90%);
}
.gate-card {
  width: 340px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  text-align: center;
  background: var(--bg-raised);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 34px 28px;
  box-shadow: var(--shadow-lg);
  animation: rise 0.3s var(--ease);
}
.gate-mark {
  width: 38px;
  height: 38px;
  border-radius: 50%;
  background: var(--accent);
  color: var(--accent-text);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  box-shadow: 0 0 0 1px var(--border-strong), 0 4px 16px var(--accent-glow);
}
.gate-card h1 { font-size: 1.1rem; font-weight: 600; margin: 4px 0 0; letter-spacing: -0.015em; }
.gate-sub { color: var(--text-dim); font-size: 0.85rem; margin: 0 0 4px; }
.gate-card input {
  width: 100%;
  padding: 10px 12px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  background: var(--bg);
  color: var(--text);
  font-size: 0.95rem;
  transition: border-color 0.15s var(--ease), box-shadow 0.15s var(--ease);
}
.gate-card input:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-glow);
}
.gate-card button {
  width: 100%;
  padding: 10px 12px;
  border-radius: var(--radius-md);
  border: 1px solid transparent;
  background: var(--accent);
  color: var(--accent-text);
  font-size: 0.9rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s var(--ease), box-shadow 0.15s var(--ease);
}
.gate-card button:hover { background: var(--accent-hover); box-shadow: 0 4px 16px var(--accent-glow); }
.gate-card button:active { box-shadow: none; }
.gate-error { color: #e5484d; font-size: 0.85rem; min-height: 1.2em; margin: 0; }

/* App layout */
.app {
  height: 100%;
  display: flex;
  position: relative;
  overflow: hidden;
}

.sidebar {
  width: 244px;
  flex-shrink: 0;
  background: var(--bg-sidebar);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  padding: 12px;
  gap: 6px;
}

.sidebar-header {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 6px 6px 14px;
}
.brand-mark {
  width: 26px;
  height: 26px;
  border-radius: 50%;
  background: var(--accent);
  color: var(--accent-text);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.8rem;
  flex-shrink: 0;
  box-shadow: 0 2px 8px var(--accent-glow);
}
.brand-name { font-weight: 600; font-size: 0.9rem; letter-spacing: -0.015em; }

.sidebar-backdrop { display: none; }

.new-chat-btn, .logout-btn {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 10px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  background: var(--bg-raised);
  color: var(--text);
  cursor: pointer;
  font-size: 0.85rem;
  text-align: left;
  transition: background 0.12s var(--ease), border-color 0.12s var(--ease), transform 0.12s var(--ease), box-shadow 0.12s var(--ease);
}
.new-chat-btn svg, .logout-btn svg { flex-shrink: 0; opacity: 0.7; }
.new-chat-btn:hover, .logout-btn:hover {
  background: var(--bg-hover);
  border-color: var(--border-strong);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}
.new-chat-btn {
  border-color: transparent;
  background: var(--accent);
  color: var(--accent-text);
  font-weight: 600;
  box-shadow: 0 2px 10px var(--accent-glow);
}
.new-chat-btn svg { opacity: 1; }
.new-chat-btn:hover {
  background: var(--accent-hover);
  border-color: transparent;
  box-shadow: 0 4px 16px var(--accent-glow);
}
.new-chat-btn:active, .logout-btn:active { background: var(--border); transform: translateY(0); box-shadow: none; }
.logout-btn.danger:hover { border-color: #e5484d; color: #e5484d; }
.logout-btn.danger:hover svg { color: #e5484d; opacity: 1; }

.sidebar-search {
  display: flex;
  align-items: center;
  gap: 7px;
  margin: 10px 2px 4px;
  padding: 6px 9px;
  border-radius: var(--radius-md);
  border: 1px solid transparent;
  background: transparent;
  color: var(--text-dim);
  transition: border-color 0.12s var(--ease), background 0.12s var(--ease);
}
.sidebar-search:hover { background: var(--bg-hover); }
.sidebar-search:focus-within { border-color: var(--accent); background: var(--bg-raised); }
.sidebar-search svg { flex-shrink: 0; opacity: 0.7; }
.sidebar-search input {
  border: none;
  background: transparent;
  outline: none;
  color: var(--text);
  font-size: 0.82rem;
  width: 100%;
  font-family: inherit;
}
.sidebar-search input::placeholder { color: var(--text-dim); }

.history-list {
  flex: 1;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 1px;
  margin-top: 6px;
}
.history-item {
  position: relative;
  display: flex;
  align-items: center;
  gap: 4px;
  padding: 8px 6px 8px 12px;
  border-radius: var(--radius-sm);
  font-size: 0.83rem;
  color: var(--text-dim);
  cursor: pointer;
  border-left: 2px solid transparent;
  transition: background 0.12s var(--ease), color 0.12s var(--ease), border-color 0.12s var(--ease), box-shadow 0.12s var(--ease);
}
.history-item:hover { background: var(--bg-hover); color: var(--text); box-shadow: inset 0 0 0 1px var(--border); }
.history-item.active { background: var(--bg-hover); color: var(--text); border-left-color: var(--accent); }
.history-item-title {
  flex: 1;
  min-width: 0;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.history-item-title[contenteditable="true"] {
  white-space: normal;
  outline: none;
  background: var(--bg);
  border-radius: var(--radius-xs);
  padding: 0 3px;
  box-shadow: 0 0 0 1px var(--accent);
}
.history-item-actions {
  display: flex;
  gap: 2px;
  opacity: 0;
  flex-shrink: 0;
  transition: opacity 0.12s var(--ease);
}
.history-item:hover .history-item-actions { opacity: 1; }
.history-item-actions button {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 26px;
  height: 26px;
  border: 1px solid transparent;
  background: transparent;
  color: var(--text-dim);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: background 0.1s var(--ease), color 0.1s var(--ease), border-color 0.1s var(--ease), transform 0.1s var(--ease);
}
.history-item-actions button svg { width: 14px; height: 14px; }
.history-item-actions button:hover {
  background: var(--border-strong);
  border-color: var(--border-strong);
  color: var(--text);
  transform: scale(1.08);
}
.history-item-actions button.danger:hover { color: #e5484d; border-color: #e5484d; }

.main {
  flex: 1;
  display: flex;
  flex-direction: column;
  min-width: 0;
}

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 16px;
  flex-shrink: 0;
  border-bottom: 1px solid var(--border);
}

.icon-btn {
  display: none;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border-radius: var(--radius-md);
  border: 1px solid transparent;
  background: transparent;
  color: var(--text);
  cursor: pointer;
  transition: background 0.12s var(--ease), border-color 0.12s var(--ease);
}
.icon-btn:hover { background: var(--bg-hover); border-color: var(--border-strong); box-shadow: var(--shadow-sm); }

.topbar-right {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-left: auto;
}

.theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  background: var(--bg-raised);
  color: var(--text);
  cursor: pointer;
  transition: background 0.12s var(--ease), border-color 0.12s var(--ease), transform 0.12s var(--ease), box-shadow 0.12s var(--ease);
}
.theme-toggle:hover {
  background: var(--bg-hover);
  border-color: var(--border-strong);
  transform: translateY(-1px) rotate(-8deg);
  box-shadow: var(--shadow-md);
}
.theme-toggle .icon-moon { display: none; }
:root[data-theme="dark"] .theme-toggle .icon-sun { display: none; }
:root[data-theme="dark"] .theme-toggle .icon-moon { display: block; }
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .theme-toggle .icon-sun { display: none; }
  :root:not([data-theme="light"]) .theme-toggle .icon-moon { display: block; }
}

.effort-select {
  display: flex;
  background: var(--bg-raised);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 2px;
}
.effort-btn {
  display: flex;
  align-items: center;
  gap: 6px;
  border: none;
  background: transparent;
  color: var(--text-dim);
  font-size: 0.78rem;
  font-weight: 500;
  padding: 6px 12px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: background 0.15s var(--ease), color 0.15s var(--ease);
}
.effort-btn svg { opacity: 0.55; transition: opacity 0.15s var(--ease); }
.effort-btn:hover { color: var(--text); }
.effort-btn:hover svg { opacity: 0.8; }
.effort-btn.active {
  background: var(--bg-hover);
  color: var(--text);
  box-shadow: inset 0 0 0 1px var(--border-strong);
}
.effort-btn.active svg { opacity: 1; color: var(--accent); }

.messages-wrap {
  position: relative;
  flex: 1;
  min-height: 0;
  display: flex;
}

.messages {
  flex: 1;
  overflow-y: auto;
  padding: 20px 0 8px;
}

.scroll-bottom {
  position: absolute;
  bottom: 14px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-strong);
  background: var(--bg-raised);
  color: var(--text);
  cursor: pointer;
  box-shadow: var(--shadow-md);
  transition: background 0.12s var(--ease), transform 0.12s var(--ease);
  z-index: 5;
}
.scroll-bottom:hover { background: var(--bg-hover); transform: translateX(-50%) translateY(-2px); }

.empty-state {
  height: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  color: var(--text-dim);
  gap: 22px;
  padding: 0 24px;
  animation: rise 0.3s var(--ease);
  background-image:
    radial-gradient(var(--border-strong) 1px, transparent 1px);
  background-size: 22px 22px;
  background-position: center;
  -webkit-mask-image: radial-gradient(ellipse 60% 55% at 50% 50%, #000 30%, transparent 85%);
  mask-image: radial-gradient(ellipse 60% 55% at 50% 50%, #000 30%, transparent 85%);
}
.empty-mark {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--accent);
  color: var(--accent-text);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 16px var(--accent-glow);
}
.empty-mark svg { width: 22px; height: 22px; }
.empty-state h2 {
  color: var(--text);
  font-weight: 600;
  margin: 0;
  font-size: 1.4rem;
  letter-spacing: -0.02em;
}

.suggestions {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 8px;
  max-width: 560px;
}
.suggestion-chip {
  border: 1px solid var(--border);
  background: var(--bg-raised);
  color: var(--text);
  padding: 8px 14px;
  border-radius: var(--radius-md);
  font-size: 0.83rem;
  cursor: pointer;
  transition: border-color 0.12s var(--ease), background 0.12s var(--ease), transform 0.12s var(--ease), box-shadow 0.12s var(--ease);
}
.suggestion-chip:hover {
  border-color: var(--accent);
  background: var(--accent-wash);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}
.suggestion-chip:active { transform: translateY(0); box-shadow: none; }

.msg-row {
  max-width: 760px;
  margin: 0 auto 20px;
  padding: 0 24px;
  display: flex;
  align-items: flex-start;
  gap: 12px;
  animation: rise 0.2s var(--ease);
}
.msg-row.user { justify-content: flex-end; }

@keyframes rise {
  from { opacity: 0; transform: translateY(4px); }
  to { opacity: 1; transform: translateY(0); }
}

.avatar {
  flex-shrink: 0;
  width: 26px;
  height: 26px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.85rem;
  font-weight: 600;
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
}
.avatar.assistant {
  background: var(--accent);
  color: var(--accent-text);
  border-color: transparent;
  box-shadow: 0 2px 8px var(--accent-glow);
}
.avatar.user {
  background: var(--bg-hover);
  color: var(--text-dim);
}
.msg-row.user .avatar { order: 2; }

.bubble-col { display: flex; flex-direction: column; gap: 4px; max-width: 100%; min-width: 0; }
.msg-row.user .bubble-col { align-items: flex-end; }

.bubble {
  max-width: 100%;
  line-height: 1.6;
  font-size: 0.92rem;
  position: relative;
}
.msg-row.user .bubble {
  background: var(--bg-bubble-user);
  padding: 9px 14px;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
}
.msg-row.assistant .bubble { padding: 3px 0; }
.bubble p { margin: 0 0 0.8em; }
.bubble p:last-child { margin-bottom: 0; }
.bubble pre {
  background: var(--code-bg);
  border-radius: var(--radius-md);
  padding: 0;
  overflow: hidden;
  font-size: 0.83rem;
  border: 1px solid var(--border);
}
.bubble pre code {
  display: block;
  padding: 12px 14px;
  overflow-x: auto;
  background: none;
  font-family: "SF Mono", ui-monospace, Menlo, Consolas, monospace;
}
.bubble code {
  background: var(--code-bg);
  padding: 1px 5px;
  border-radius: var(--radius-xs);
  font-size: 0.88em;
  font-family: "SF Mono", ui-monospace, Menlo, Consolas, monospace;
}
.bubble ul, .bubble ol { margin: 0 0 0.8em; padding-left: 1.3em; }
.bubble li { margin: 0.2em 0; }
.bubble h1, .bubble h2, .bubble h3, .bubble h4 {
  margin: 0.9em 0 0.4em;
  font-weight: 600;
  letter-spacing: -0.015em;
  line-height: 1.3;
}
.bubble h1:first-child, .bubble h2:first-child, .bubble h3:first-child, .bubble h4:first-child { margin-top: 0; }
.bubble h3 { font-size: 1.05em; }
.bubble h4 { font-size: 1em; }
.bubble blockquote {
  margin: 0 0 0.8em;
  padding: 2px 12px;
  border-left: 2px solid var(--border-strong);
  color: var(--text-dim);
}
.bubble hr { border: none; border-top: 1px solid var(--border); margin: 1em 0; }
.bubble a { color: var(--accent); text-decoration: underline; text-underline-offset: 2px; }
.bubble a:hover { color: var(--accent-hover); }

.code-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 6px 8px 6px 12px;
  background: var(--bg-hover);
  border-bottom: 1px solid var(--border);
  font-size: 0.72rem;
  color: var(--text-dim);
  text-transform: lowercase;
  letter-spacing: 0.02em;
  font-family: "SF Mono", ui-monospace, Menlo, Consolas, monospace;
}
.copy-btn {
  display: flex;
  align-items: center;
  gap: 5px;
  border: 1px solid transparent;
  background: transparent;
  color: var(--text-dim);
  font-size: 0.72rem;
  padding: 3px 7px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: background 0.12s var(--ease), color 0.12s var(--ease), border-color 0.12s var(--ease);
}
.copy-btn:hover { background: var(--border-strong); color: var(--text); }

.msg-toolbar {
  display: flex;
  gap: 2px;
  opacity: 0;
  transition: opacity 0.12s var(--ease);
}
.msg-row:hover .msg-toolbar { opacity: 1; }
.msg-toolbar button {
  display: flex;
  align-items: center;
  gap: 5px;
  border: 1px solid var(--border);
  background: var(--bg-hover);
  color: var(--text-dim);
  font-size: 0.7rem;
  padding: 3px 8px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: background 0.12s var(--ease), color 0.12s var(--ease), border-color 0.12s var(--ease);
}
.msg-toolbar button:hover { background: var(--border-strong); border-color: var(--border-strong); color: var(--text); }

.typing-dot {
  display: inline-block;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--accent);
  animation: blink 1.2s infinite ease-in-out;
}

@keyframes blink {
  0%, 80%, 100% { opacity: 0.2; }
  40% { opacity: 1; }
}

.error-bubble { color: #e5484d; font-size: 0.88rem; }

.composer {
  max-width: 760px;
  margin: 0 auto;
  width: 100%;
  padding: 10px 24px 20px;
}
.composer-box {
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  background: var(--bg-raised);
  box-shadow: var(--shadow-sm);
  transition: border-color 0.15s var(--ease), box-shadow 0.15s var(--ease);
  overflow: hidden;
}
.composer-box:focus-within {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-glow);
}
.composer textarea {
  display: block;
  width: 100%;
  resize: none;
  border: none;
  background: transparent;
  color: var(--text);
  padding: 12px 14px 4px;
  font-size: 0.92rem;
  font-family: inherit;
  max-height: 200px;
}
.composer textarea:focus { outline: none; }
.composer-footer {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 6px;
  padding: 0 8px 6px 14px;
}
.token-estimate {
  margin-right: auto;
  font-size: 0.7rem;
  color: var(--text-dim);
  opacity: 0.8;
}
.composer-tool {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 26px;
  height: 26px;
  border: 1px solid var(--border);
  background: var(--bg-hover);
  color: var(--text-dim);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: background 0.12s var(--ease), color 0.12s var(--ease), border-color 0.12s var(--ease);
}
.composer-tool:hover { background: var(--border-strong); border-color: var(--border-strong); color: var(--text); }
.composer button#send {
  flex-shrink: 0;
  width: 30px;
  height: 30px;
  margin-left: 4px;
  border-radius: 50%;
  border: 1px solid transparent;
  background: var(--accent);
  color: var(--accent-text);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 2px 8px var(--accent-glow);
  transition: background 0.12s var(--ease), box-shadow 0.12s var(--ease), transform 0.12s var(--ease);
}
.composer button#send:hover:not(:disabled) {
  background: var(--accent-hover);
  box-shadow: 0 3px 14px var(--accent-glow);
  transform: translateY(-1px);
}
.composer button#send:disabled { opacity: 0.4; cursor: default; }
.composer button#send.stopping { background: var(--bg-hover); color: var(--text); }
.composer button#send.stopping:hover { background: var(--border-strong); }

@media (max-width: 700px) {
  .sidebar {
    position: fixed;
    top: 0;
    left: 0;
    bottom: 0;
    z-index: 20;
    transform: translateX(-100%);
    transition: transform 0.2s var(--ease);
    box-shadow: var(--shadow-lg);
  }
  .sidebar.open { transform: translateX(0); }
  .sidebar-backdrop {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.5);
    z-index: 15;
  }
  .sidebar-backdrop.open { display: block; }
  .icon-btn { display: flex; }
  .effort-btn span { display: none; }
  .effort-btn { padding: 7px 9px; }
}